Furthermore, the cardiopulmonary exercise test is useful for the classification of cardiovascular risk, the prescription of physical exercise and for the functional evaluation of the person who undergoes it.
This test, also known as the graded exercise test (or GXT), is able to examine the reactions of the cardiovascular system during physical exercise and to highlight any changes that are not found at rest.
Analysing the cardiopulmonary exercise test
During the cardiopulmonary exercise test, however, the patient is subjected to increases in the workload of gradual intensity, which increase at fixed intervals of time.
Thanks to the cardiopulmonary exercise test, the effort required of the patient leads to an increase in heart rate and blood pressure, and consequently to an increased demand for blood from the heart.
How to perform a cardiopulmonary exercise test
In both protocols, a warm-up phase is followed by the actual training phase, in which the resistance (in the case of the bike) or the inclination and speed (in the case of the treadmill) is increased at regular intervals of time. The protocol ends when a certain heart rate is reached or when the patient is unable to continue the exercise.
Why is the cardiopulmonary exercise test useful?
This test is also indicated for subjects potentially affected by ischaemic heart disease, providing information on the blood flow through the coronary arteries, reducing the risk of coronary atherosclerosis.
In practice, this heart disease reduces the blood supply in a body district, causing a decrease in the supply of oxygen and other nutrients and in the ability to eliminate waste substances.
When to use and not to use the CPET
However, the cardiopulmonary exercise test is not indicated in all conditions. If the patient shows severe cardiovascular instability, respiratory failures, episodes of embolism or recent heart attacks, it is not recommended to use CPET in favour of other tests, such as ECG at rest.